Radiation oncology journal最新文献

Purpose: This study aimed to evaluate treatment outcomes with associated prognostic factors, and to guide treatment strategies in colorectal cancer patients with oligometastatic disease (OMD) treated with stereotactic body radiotherapy (SBRT).

Materials and methods: This retrospective study included 74 colorectal cancer patients who received SBRT for 113 lesions (88 lung, 19 liver, and 6 lymph node). Each OMD was considered a separate case for patients repeatedly diagnosed with OMD. The log-rank test and Cox proportional hazards model were used to assess prognostic factors for progression-free survival (PFS).

Results: A total of 84 cases were analyzed. The median follow-up period was 32.2 months (range, 8.2 to 89.3 months). The 2-year PFS, widespread failure-free survival (WSFFS), and overall survival (OS) rates were 35.1%, 67.4%, and 80.8%, respectively. In the multivariable analysis, oligometastatic status (repeat/induced vs. de novo; hazard ratio [HR], 2.66; 95% confidence interval [CI], 1.40 to 5.04; p = 0.003) and planning target volume (PTV) volume (17.6 vs. <17.6 cm3; HR, 1.99; 95% CI, 1.09 to 3.62; p = 0.025) were significant prognostic factors for PFS. Cases with two risk factors for PFS demonstrated significantly worse OS and WSFFS (p < 0.05), whereas those with one risk factor did not show a significant difference compared to cases with no risk factors.

Conclusion: SBRT for oligometastatic colorectal cancer showed favorable clinical outcomes. Oligometastatic status and PTV volume were significantly associated with PFS. Risk stratification based on the number of poor prognostic factors of PFS may help guide treatment strategies for colorectal cancer patients with OMD.

Purpose: High-dose-rate (HDR) brachytherapy is a promising treatment modality for organ and function preservation in lip and oral cavity cancers. This study aims to describe the technique and assess clinical outcomes of HDR interstitial brachytherapy in patients diagnosed with lip and buccal mucosa cancer treated in a comprehensive cancer center.

Materials and methods: We conducted a retrospective analysis of six lip and four buccal mucosa cancer patients with a median age of 69 years (range, 37 to 90) and equal gender distribution, who underwent exclusive interstitial brachytherapy during the study period from May 2019 to December 2024. All procedures were performed under local anesthesia. Most patients were treated with HDR brachytherapy with a total dose of 40 Gy in 10 fractions over 5 days. Patient characteristics, treatment parameters, cosmetic and functional outcomes, and toxicity were assessed.

Results: All patients in this cohort achieved local control and remained in remission at the treatment site throughout the follow-up period. The median duration of follow-up was 29 months (range, 16 to 68). Cosmetic outcomes were rated as good in most of the patients. Any acute and late toxicities experienced were manageable; the most severe acute toxicity observed was grade 3, with late toxicity reaching grade 2.

Conclusion: Favorable tumor control, good aesthetic results with manageable toxicity, and the minimally invasive approach highlight interstitial brachytherapy as a compelling single treatment modality for eligible patients with lip and buccal mucosa cancer, particularly in older individuals with significant comorbidities.

Purpose: This study aimed to compare treatment outcomes between patients who received adjuvant radiotherapy (RT) and those who did not, in a cohort of patients with low-risk, early-stage breast cancer.

Materials and methods: Postmenopausal women with pT1N0/Nx, grade 1-2, hormone receptor-positive, human epidermal growth factor 2-negative, and Ki-67 ≤ 20% breast cancer who underwent breast-conserving surgery and adjuvant endocrine therapy between 2010 and 2020 were included. The decision on RT omission was based on physician assessment and patient preference. The primary outcome was cumulative incidence of disease recurrence. Secondary outcomes included locoregional recurrence, overall survival, and breast cancer-specific survival.

Results: Of the 742 patients, 707 received adjuvant RT (postoperative radiation therapy [PORT] group) and 35 did not (RT omission group). Baseline characteristics were generally similar; however, the RT omission group was older (median age, 76 years; range, 68 to 85 years) than the PORT group (median age, 62 years; range, 55 to 87 years). After a median follow-up of 60 months in the PORT group and 52 months in the RT omission group, the 5-year cumulative incidence of disease recurrence was 1.28% and 0%, respectively (Gray's test, p = 0.305). Locoregional recurrence occurred in seven patients (1.0%) in the PORT group, whereas no locoregional recurrences were observed in the RT omission group. The results remained consistent after propensity score matching.

Conclusion: Low-risk, early-stage breast cancer patients exhibited comparable disease recurrence and survival rates regardless of the RT status. Our study underscores the necessity for further investigation into RT omission in carefully selected patients.

Purpose: This study aimed to investigate retrospectively the feasibility of reducing the standard postoperative radiation therapy (PORT) dose of 45-50 Gy for locally invasive thymoma to shorten treatment duration and minimize side effects, while preserving disease-specific survival (DSS) and progression-free survival (PFS).

Materials and methods: Between January 2016 and June 2022, 150 locally advanced thymoma patients underwent surgery followed by intensity-modulated radiation therapy, with a median follow-up of 40.8 months; the standard regimen was 45-50 Gy in 25 fractions (median biological effective dose [BED] 60 Gy), compared to a de-escalation regimen of 30-35 Gy in 10 fractions (median BED 47.25 Gy), with PFS as the primary endpoint, and overall survival (OS), DSS, and toxicity as secondary endpoints.

Results: No significant differences were found between standard and de-escalation groups in 3-year PFS (p = 0.406), with both groups achieving 100% 3-year DSS; two deaths in the de-escalation group were due to double primary cancers. All locoregional recurrences occurred outside the radiation field. Factors including age, initial tumor size, myasthenia gravis, and pathological type showed no correlation with PFS or OS. No grade II toxicities occurred in the de-escalation group, whereas the standard group had three cases of grade II toxicity, specifically radiation pneumonitis.

Conclusion: Radiation dose de-escalation in locally advanced thymoma patients undergoing PORT showed comparable survival outcomes with reduced toxicity and shorter treatment duration, but requires longer follow-up to confirm efficacy and safety.

Purpose: This study aimed to evaluate the effect of radiotherapy (RT) on symptomatic relief and tumor control in patients with breast cancer with skin involvement.

Materials and methods: This retrospective study included patients who received palliative RT of the breast or chest wall for breast cancer with skin involvement. Progression-free survival, freedom from local progression (FFLP), and symptomatic response were evaluated. The prescribed dose to tumor was calculated as the biologically effective dose (BED) using α/β of 4. Symptomatic responses were evaluated until 6 months after RT.

Results: Of the 43 patients included in this study, 48 Gy in 15 fractions was the most common regimen, and the median BED was 86.4 Gy (range, 24.0 to 120.0). With a median follow-up of 15.1 months (range, 1.6 to 63.5), the median FFLP and progression-free survival were 8.4 and 3.6 months, respectively. The 1-year FFLP rates in patients who received BED >75 Gy and BED ≤75 Gy were 78.3% and 49.7%, respectively (p = 0.046). Within 6 months after RT, 75% of patients showed relief of discharge, 67% showed relief of bleeding, and 37% showed relief of pain. There was no grade 3 or higher skin toxicity or other adverse events.

Conclusion: Palliative RT is a safe and effective treatment option for patients with breast cancer with skin involvement, providing symptomatic relief. The administration of BED ≥75 Gy can offer a benefit in achieving durable local control.

Purpose: Our purpose was to compare four whole brain radiotherapy (WBRT) delivery types: opposed lateral (OL) 3-dimensional-conformal radiotherapy (3D-CRT), a novel opposed lateral sparing (OLS) 3D-CRT technique, 3D optimized dynamic conformal arcs (optDCA), and hippocampal-avoidant WBRT (HA-WBRT).

Materials and methods: Ten patients previously undergoing HA-WBRT were retrospectively planned using OL, OLS, and optDCA techniques. OLS technique involved multi-leaf collimator (MLC) modifications to protect the lacrimal and parotid glands. OptDCA was inverse-planned 3D-CRT with dynamic conformal arcs. A dosimetric, cost, and resource utilization comparison was performed.

Results: Planning target volume coverage to prescription dose between 3D planning techniques was not significantly different between OL and OLS techniques (96.8% vs. 96.6%, p = 0.855), or between OL, OLS, and optDCA (95.0%) techniques (p = 0.079). There was no difference in the heterogeneity index between 3D plans (p = 0.482); all were less heterogeneous than HA-WBRT (p < 0.001). OptDCA was more conformal than OL and OLS, and similar in conformity to HA-WBRT. OLS achieved significant sparing of lacrimal and parotid glands over OL. There were significant step-function reductions in organ at risk (OAR) dose when comparing OL to OLS to optDCA to HA-WBRT plans. HA-WBRT was 57% more expensive than OL and OLS technique. HA-WBRT took approximately six times longer to plan.

Conclusion: We showed adequate and equivalent target coverage using OL, OLS, and optDCA techniques. Lacrimal and parotid dosages can be greatly reduced with the implementation of minor MLC adjustments. OptDCA therapy represented further improvement of these modifications, and was comparable to HA-WBRT in terms of OAR dose, while being about two-thirds the cost and more efficient to plan.

Radiation-induced cutaneous side effects are well known; however, the isoradiotopic phenomenon presenting as lichen planus is underreported in the literature. It is imperative to be aware of this entity to manage the patients accordingly. Herein, we report a 31-year-old male, a known case of carcinoma glottis who developed lichen planus confined to the radiation site and presented with a review of literature on isoradiotopic lichen planus.

Purpose: Stereotactic radiotherapy (SRT) is an important adjunctive treatment after excision of brain metastases. We investigated efficacy and safety outcomes of such treatment and the impact of radiotherapy dose fractionations in a real-world multi-center cohort.

Materials and methods: All patients who received resection cavity SRT between 2018-2022 were identified from institutional databases of two tertiary oncology centers. Patient and treatment characteristics were summarized using descriptive statistics. Local control rate (LCR), distant brain control rate (DBCR), and overall survival (OS) were estimated. Prognostic factors were investigated using univariate/multivariate Cox regression. The incidence of radiation necrosis (RN) was reported.

Results: Sixty-five cavities were analyzed. The most used SRT prescription was 30 Gy/5 fractions. One-year LCR, DBCR, and OS were 69.0%, 51.9%, and 71.0%, respectively. BED10 (biological effective dose using α/β ratio of 10) was a significant factor for improved local control on both univariate (hazard ratio [HR], 0.862; 95% confidence interval [CI], 0.787 to 0.944; p = 0.001) and multivariate analysis (HR, 0.890; 95% CI, 0.803 to 0.986; p = 0.026). Cavities prescribed BED10 ≥45 Gy had superior local control than those prescribed BED10 <45 Gy (p = 0.002). The rate of RN was 6.2%. Single-fraction treatment had higher rates of RN (p = 0.030). There was no significant difference in LCR between single-fraction and fractionated subgroups in cavities with BED10 ≥45 Gy (p = 0.542).

Conclusion: BED10 independently predicts LCR in resection cavity SRT. Fractionated treatment is associated with a lower risk of RN and did not appear to compromise outcomes as long as prescription BED10 ≥45 Gy.